Numerous wheelchairs have been developed for both residential and commercial use, including motorized wheelchairs. Some of these have provided limited vertical adjustability, and others have attempted to permit transfer of a occupant either onto or off of the wheelchair, such as by providing a removable seat. These prior structures, however, have proven to be less than desirable since most have not provided both a durable and simple structure while permitting vertical adjustability, nor have they provided a structure which can be safely and conveniently manipulated to permit transfer of the occupant, such as when the seat is being transferred.
Rather, particularly in medical facilities, transfer of patients is still accomplished primarily by using lift devices wherein a wheeled frame is provided with a single vertically extendable upright post having a support arm projecting cantilevered from the upper end thereof, which arm at its free end has a slinglike flexible seat suspended therefrom for supporting a patient. Such mechanisms do not function as wheelchairs, however, but solely as lifting and transfer devices. Further, such devices are frightening to the patient since the patient is supported solely by the suspended flexible seat arrangement and does not have the comfort and security of being seated within a chair structure.
With respect to wheelchairs which have been developed for home use, while many such chairs have been motorized, nevertheless the known chairs have either provided no or only limited capability of permitting the occupant to raise and lower the seat, and have not permitted transfer from the chair. While various complex specialized chairs and transfer mechanisms have been developed to assist in transferring the patient into or out of a vehicle, including transfer to or from the vehicle and the wheelchair, nevertheless most of these devices have been extremely specialized, cumbersome and expensive, and hence have not permitted simplified and efficient transfer from a seemingly conventional wheelchair.
Accordingly, it is an object of the present invention to provide an improved wheelchair which is believed to represent a significant improvement over many of the wheelchairs and lifting devices which have been heretofore utilized.
More specifically, it is an object of this invention to provide an improved wheelchair which can be utilized so as to function in a manner which corresponds to a conventional wheelchair, whereby an occupant can comfortably sit in and comfortably utilize the wheelchair, but which also provides greatly improved flexibility in terms of permitting transporting and transferring of the occupant. In particular, the improved wheelchair includes improved capability of permitting raising and lowering of the occupant, and at the same time permitting transferring of the occupant either onto or off of the wheelchair by means of a seat arrangement which can be readily attached to or detached from the wheelchair.
A further object of the invention is to provide an improved wheelchair, as aforesaid, which in one variation is particularly desirable for use in medical facilities so as to improve the transportability and transferability of patients in a safe and secure manner while requiring only minimal assistance from the medical facility personnel, such as permitting transfer of a patient while being assisted by only a single person.
Still a further object of the invention is to provide a wheelchair which, in a further variation, is self-propelled and highly desirable for use in a residence or the like so as to enable the occupant to control his/her own movement throughout the building, which wheelchair enables the occupant to have significant control over the vertical height of the seat to greatly improve the flexibility of the chair, and at the same time permits the occupant to be readily transferred to or from the chair, such as permitting transfer into a vehicle or the like.
Another object of the invention is to provide a wheelchair, as aforesaid, which is durable and relatively simple in construction, and is also economical to manufacture.